She had been training diligently, so she performed exceptionally well in the competition.
He had been studying intensively, so he aced the exam.
In these sentences, the past perfect continuous tense helps us express the cause-and-effect relationship between an ongoing action or activity and its resulting outcome or consequence in the past. It emphasizes the connection between the preceding action or activity and its impact.
It is important to note that the past perfect continuous tense is often accompanied by time expressions or specific durations to provide additional context or specify the timeframe of the ongoing action or activity. Here are some common time expressions used with the past perfect continuous tense:
For, since
All day, all week, all month, all year
By the time, when
how long
These time expressions help to provide further clarity and precision to our statements when using the past perfect continuous tense.